There is a well-recognized need for environmental remediation, or cleanup, of contaminants that exist in a variety of settings. For example, radioactive waste and other contaminants from a variety of reactor experiments have been previously disposed of in various locations by placing the contaminants in waste containers buried underground. These buried waste containers, such as silos and vertical pipe units (VPUs) contain contaminants that may pose a threat to the environment, and ultimately to the health and safety of all living creatures. Recent efforts have been made to remove and more securely dispose of hazardous waste from such buried waste containers.
During remediation, field operators often may not know of the radiation strength or contents of the buried waste container until after excavation of the buried waste container has already begun. This may make it difficult for field operators to develop a proper remediation plan to ensure efficiency of the clean up as well as provide the proper safeguards for safety in handling the waste during removal. For example, prior efforts to characterize radioactive contents of buried waste containers included uncovering portions of the waste through excavation, partially exposing portions of the buried waste container before knowing anything regarding its contents. With part of the waste container exposed, single detectors, such as a Geiger Mueller detector, have been used to detect the strength of radiation field but without knowing the contents of the container. Once a first set of measurements is taken, prior methods include excavating further and taking additional measurements.
During environmental remediation of radioactive waste sites, there is a need for in-situ characterization of the waste, including obtaining immediate information on the distribution and quantities of radioactive material present. This information may be used to make immediate decisions regarding specific remediation requirements. Further, there is a need to have a system that works in a wide range of radiation environments with the capability to provide synergistic data from a range of sensors on the types and quantities of radioactive material present. Additionally, material detection systems may be operated by persons with limited training. Thus, a system is desired such that untrained operators can easily calibrate and operate the system, and interpret the output of the system for making environmental remediation decisions at waste sites.